Simple, rapid and effective preservation and reactivation of anaerobic ammonium oxidizing bacterium Candidatus Brocadia sinica

• Published in: Water research (Oxford) Vol. 57; pp. 215 - 222
• Main Authors: ALI, Muhammad, OSHIKI, Mamoru, OKABE, Satoshi
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier 01.06.2014
• Subjects: Activation; Alginates - metabolism; Ammonia - metabolism; Anaerobic processes; Applied sciences; Bacteria; Bacteria, Anaerobic - genetics; Bacteria, Anaerobic - isolation & purification; Bacteria, Anaerobic - physiology; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Biological and medical sciences; Biological treatment of waters; Biomass; Biotechnology; Environment and pollution; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General purification processes; Genes; Glucuronic Acid - metabolism; Hexuronic Acids - metabolism; Industrial applications and implications. Economical aspects; Molybdates; Molybdenum - chemistry; Nitrogen - metabolism; Nutrients; Oxidation; Oxidation-Reduction; Planctomycetales - genetics; Planctomycetales - isolation & purification; Planctomycetales - physiology; Pollution; Polyvinyl Alcohol - metabolism; Preservation; Preservation, Biological - methods; Real-Time Polymerase Chain Reaction; Time Factors; Wastewaters; Water treatment and pollution; Reactor start-up; Water treatment; Ammonium; Anammox process; Nitrogen compounds; Immobilization; Preservation of anammox biomass; Start-up of anammox reactor; Microbial biomass; Biological purification; Enzymatic activity; Anaerobe; Cryopreservation; hzsA gene expression; Bacteria; Oxidation; Waste water purification; Entrapped microorganism
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/j.watres.2014.03.036

It is still the biggest challenge to secure enough seeding biomass for rapid start-up of full-scale (anaerobic ammonium oxidation) anammox processes due to slow growth. Preservation of active anammox biomass could be one of the solutions. In this study, biomass of anammox bacterium, "Candidatus Brocadia sinica", immersed in various nutrient media were preserved at -80 °C, 4 °C and room temperature. After 45, 90 and 150 days of preservation, specific anammox activity (SAA) of the preserved anammox biomass was determined by measuring (29)N2 production rate and transcription levels of hzsA gene encoding hydrazine synthase alpha subunit. Storage in nutrient medium containing 3 mM of molybdate at room temperature with periodical (every 45 days) supply of NH4(+) and NO2(-) was proved to be the most effective storage technique for "Ca. Brocadia sinica" biomass. Using this preservation condition, 96, 92 and 65% of the initial SAA was sustained after 45, 90 and 150 days of storage, respectively. Transcription levels of hzsA gene in biomass correlated with the SAA (R(2) = 0.83), indicating it can be used as a genetic marker to evaluate the anammox activity of preserved biomass. Furthermore, the 90-day-stored biomass was successfully reactivated by immobilizing in polyvinyl alcohol (6%, w/v) and sodium alginate (2%, w/v) gel and then inoculated to up-flow column reactors. Total nitrogen removal rates rapidly increased to 7 kg-N m(-3) d(-1) within 35 days of operation. Based on these results, the room temperature preservation with molybdate addition is simple, cost-effective and feasible at a practical scale, which will accelerate the practical use of anammox process for wastewater treatment.